Extractor mechanism for firearms



Feb. 4, 1964 Filed Feb. 5, 1963 H. M. PERNINI 3,120,071

EXTRACTOR MECHANISM FOR FIREARMS 2 Sheets-Sheet 1 I/ ////l l4! IY Ill 0 F 43 4| 49 45 1/ III III BYZMA'W,

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EXTRACTOR MECHANISM FOR FIREARMS Filed Feb. 5, 1963 2 Sheets-Sheet 2 III/III] \LII/I/Il/l/II/ IIIIIIIIIIIL Ill/l Ill/J1 III I I/ II III III/7] V/l/ I I 49 K, I r5 IjI/l I 4? 43 6 INVENTOR.

HENRY M.PERNIN| BYZMJ-MI United States Patent 3,12tl,071 EXTRACTOR MECHANISM FOR FIREARMS Henry M. Pernini, Chicago, Ill.,. assignor, by mesne assignments, to the United States of America as represented by the Secretary of the Army Filed Feb. 5, 1963, Ser. No. 256,483 6 Gaims. (Cl. 42-25) The present invention relates to an extractor mechanism for firearms and more particularly to an improved extractor for an automatic or semiautomatic gun employing the constant recoil principle of operation.

A principal object of the present invention is to provide an improved extractor for automatic or semiautomatic guns which is simple, efficient, and positive in operation.

It is a further object of the present invention to pro vide an extractor mechanism for a firearm which utilizes maximum forces generated by a lever principle to extract a spent cartridge case from the chamber of the firearm.

Another object of the present invention is to provide an extractor for a firearm which is responsive to automatic operation and which will quickly and effectively eject a spent cartridge case from the firearm chamber.

In accordance with the present invention, an extractor for a recoil operated gun is provided which comprises a lever of the third class. The extractor is fulcrumed on the frame of the gun and is automatically operated by the reciprocating barrel as it moves in recoil and counterrecoil relative to the gun frame. One end of an arm of the extractor which is remote from the fulcrum point is disposed in a manner to engage the extractor groove of a cartridge case thereby to facilitate removal of the spent cartridge from the chamber. The arrangement is so constructed that primary extraction, which breaks the cartridge case from the chamber, is effected by a high force with low acceleration, and secondary extraction, which throws the case back against the guns ejector, is effected by a low force but high acceleration. This is accomplished by shifting the contact point between the barrel and a cumming surface of the extractor. Movement of the ejector is facilitated by the action of a spring pressed toggle lever which functions in an over-dead-center posi tion.

The novel features of the present invention, as well as additional objects and advantages thereof, will be understood better irom the following detailed description when read in connection with the accompanying drawings. The several drawings comprise a series of views showing the relative position of parts of the present invention during a complete cycle of operations incident to firing the gun to which it is applied. In the drawings illustrating a practicable form of the invention:

FIGURE 1 is a fragmentary, longitudinal sectional view in the vicinity of the breech portion of an automatic gun provided with an extractor in accordance with the present invention, the various parts being shown in a normal battery position preparatory to firing and certain parts thereof being broken away to show further details;

FIGURE 2 is a view similar to FIGURE 1 showing the relation of parts shortly after firing and wherein the barrel has commenced recoil action, the chamber is engaged with the extractor and the extractor is about to engage the extractor groove of a spent cartridge case;

FIGURE 3 is a view which is similar but subsequent to that of FIGURE 2 and showing the relation of parts during primary extraction;

FIGURE 4 is another view like that of FIGURE 3 but subsequent thereto and showing the relation of parts during secondary extraction;

FIGURE 5 is a view similar to FIGURE 4 but showing the relation of parts in full recoil position, a new cartridge having been chambered in the barrel; and

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FIGURE 6 is a view showing the relation of parts during counter-recoil, the extractor being shown in a position during return to normal battery position of the gun.

Referring more particularly to the drawings wherein like reference characters designate corresponding parts throughout the diiierent views, a preferred embodiment of the present invention is shown as applied to a conven tional gun mechanism. The complete gun mechanism is not shown but only those parts are shown which are necessary to an understanding of the construction and operation of the invention. For this purpose, the principal gun parts shown are the frame 1, the barrel 3, and the sliding breech block mechanism 5.

In gun mechanisms of the type to which the present invention is directed, the gun barrel recoils to the rear under the pressure of gases incident to firing the gun. Therefore, the barrel 3 is slidably mounted on the frame 1 for reciprocating movement relative thereto. The breech end 7 of the barrel is provided with a chamber 9 for receiving a cartridge ll. Rearwardly of the chamber the breech block mechanism is slidably mounted for movement upwardly in response to recoil of the gun barrel, in a manner well known in the art.

Pivotally mounted on the frame 1, at a position rearward of the chamber 9 when it is in battery position, is an extractor 13. The extractor comprises a bell crank lever having a main arm 15, a heel portion 17, and an auxiliary arm 19. The heel portion is mounted on the frame so that it provides a horizontal pivotal axis for the extractor. The pivotal axis is oriented normal to the direction of movement of the gun barrel so that the extractor will rotate in the direction of movement of the gun barrel. The auxiliary arm 19 extends from the heel portion substantially at a right angle to the main arm 15. The main arm is of a length to extend into the path of the reciprocating barrel when it is disposed normally in the battery position. 0n the other hand, the auxiliary arm is also of a length to extend into the path of the reciprocating barrel but only after the extractor has been rotated by the barrel to a rearward position. The free end of the main arm, which is remote from the heel portion 17, is provided with an extended finger-like portion 21 for engaging the extractor groove 23 of a cartridge case chambered in the barrel. Adjacent to the finger-like portion on the side thereof facing the barrel breech '7 there is provided a cam surface 25 disposed for abutment with the face 27 of the breech. The cam surface defines a curve which is designed and arranged in such manner that the point of contact between the extractor and the breech face advances toward the pivotal axis of the extractor as recoil movement of the barrel progresses.

For the purpose of locking or maintaining the extractor in either one of its positions forwardly or rearwardly, as well as to facilitate movement of the extractor, there is provided an overcenter spring mechanism 29. The spring mechanism comprises a guide rod 31 having one end mounted for longitudinal slidable movement through a post 33. The post 33 is pivotally mounted on the gun frame 1. The opposite end 35 of the rod 31 is pivotally attached to the main arm 15 at a point interjacent its ends Where it will serve to operate the extractor with an overcenter spring action. An open end, helical, compression spring 37 is disposed around the guide rod 31 between the post 33 and a collar 39 attached to the guide rod.

In order to limit movement of the extractor in either direction, a stop 41 is mounted on the gun frame beneath the extractor. The stop is provided with two faces or sides 43, 45 which are engaged by the extractor. The one side 43 is located in a position which will be engaged by a side 47 of the main arm as the extractor is rotated rear- 3 wardly during recoil action. The other side 45 is located in a position so that it will engage a side 49 of the auxiliary arm 19 of the extractor thereby to restrict or limit forward movement of the extractor during counter-recoil action.

Operation Assume the gun is ready for firing, as shown in FIG- URE 1. In this position, a cartridge 11 is chambered in the barrel 3 and the sliding breech block is locked in place wedging the round in the chamber. The position of the extractor at this time is forwardly with its auxiliary arm face 49 engaging the stop face 45. The overcenter spring mechanism 29 in this position functions to force the extractor main arm forwardly.

After firing, the barrel recoils and the breech face 27 engages the extractor main arm cam surface 25 at a point remote from the heel pivotal axis, as shown in FIGURE 2 of the drawings. During this primary extraction phase, the extractor finger-like portion 21 is forced into position under the cartridge case rim, that is, into the extractor groove 23. The sliding breech block then moves upwardly to clear the spent cartridge case. As soon as the case is clear, the finger-like portion strips or pries the case from the chamber. The recoil force imposed by the barrel moving rearwardly is applied to the extractor cam surface 25 at a point remote from the pivotal axis of the extractor. This action imposes a high force with low acceleration on the case to release it from the chamber.

As the barrel moves further in recoil, the contact point between the barrel and the camrning surface of the extractor moves closer to the extractor center of rotation thereby imparting low force but high acceleration to the expended cartridge case for the secondary extraction phase. This phase is illustrated by FIGURES 3 and 4 of the drawings. The empty case is thus thrown back against the gun ejector (not shown) and then out a slot (not shown) in the right side of the gun frame.

As the barrel moves on through recoil to the extreme position, as shown in FIGURE 5, a new round has been chambered in the barrel and the extractor has been rotated to the rearward position. It will be noted that during this movement, the rod 31 of the overcenter spring mechanism 29 has been forced rearwardly to compress the spring 37. Once the rod passes over the center line through the extractor pivotal axis, the spring exerts a turning moment on the extractor, thus driving the rod forwardly and influencing the extractor rearwardly to the position where its side 47 abuts with side 43 of the stop 41.

Once the barrel reaches a full recoil position, as shown in FIGURE 5, counterrecoil movement takes place and the barrel is moved forwardly on the frame. During this phase, the forward face 51 of a dependent portion of the barrel breech end 7 engages the auxiliary arm 19 of the extractor and forces the extractor to rotate forwardly, in the manner shown in FIGURE 6. Rotation of the extractor forwardly again moves the rod 31 rearwardly to compress the spring 37. As the rod passes over the center line through the extractor pivotal axis, the spring exerts a turning moment on the extractor thus driving the extractor forwardly to a normal battery position preparatory to firing the next round. The extractor thereby remains in this position until picked up again by the barrel during recoil.

From the foregoing description, it will be recognized by persons skilled in the art that the present invention provides a simple and eificient extractor mechanism for guns operating on a recoil principle. The lever action utilizes maximum forces not only in stripping the spent cartridge case from the chamber, but also in effecting rapid ejection of the case prior to chambering a new round. Although but a single, preferred embodiment of the present invention is shown and described herein, it will also be recognized that other embodiments are possible within the scope of the claims presented herein. Therefore, it is desired that the present invention shall not be limited except insofar as is made necessary by the prior art and by the spirit of the appended claims.

What is claimed is:

1. In a firearm having a frame and a reciprocating barrel slidably mounted thereon for movement in response to recoil forces incident to firing said firearm, said barrel having a chamber for receiving a cartridge therein, an extractor comprising a bell crank lever pivotally mounted on said frame and disposed in a normal position prior to firing of said firearm rearwardly of said barrel chamber, one arm of said lever extending normally into the path of said reciprocating barrel and having an extended end portion for engagement with the extractor groove of a cartridge chambered in said barrel, a surface portion of said one arm adjacent to said extended end portion being curved to provide a cam surface and being disposed for engagement with said barrel in response to recoil thereof, another arm of said lever being disposed for engagement by said barrel in response to counterrecoil thereof for returning said lever to its normal position and means on said frame operatively connected with said lever for biasing said lever in either direction of its movement incident to reciprocating movement of said barrel.

2. The invention as defined in claim 1 wherein said extractor cam surface defines a curve whereby the point of contact between said curved surface and said barrel advances toward the pivotal axis of said extractor in response to recoil movement of said barrel chamber.

3. The invention as defined in claim 2 wherein said biasing means comprises an overcenter spring carried by said frame and disposed to lock said extractor in either over-dead-center position.

4. The invention as defined in claim 3 and wherein stop means is carried by said frame, said stop means being disposed to limit movement of said extractor in either direction of its travel.

5. In a firearm having a frame and a barrel slidably mounted thereon for reciprocating movement in response to recoil forces incident to firing said firearm, said barrel having a chamber for receiving a cartridge therein, an extractor comprising a bell crank lever having a main arm, an auxiliary arm extending from said main arm, and a heel portion, said lever being pivotally mounted at said heel portion on said frame, said main arm extending normally into the path of said reciprocating barrel, the end of said main arm remote from said heel portion having a protruding finger portion for engaging the extractor groove of a cartridge disposed in said chamber, a surface portion of said main arm adjacent to said finger comprising a cam surface disposed for abutment with a portion of said chamber in response to recoil movement thereof, said auxiliary arm being disposed into the path of said reciprocating barrel during counterrecoil thereof for engagement by said chamber, said cam surface defining a path whereby the point of contact with said chamber advances toward said level pivotal connection in response to rotation of said lever as a result of recoil movement of said barrel, and means on said frame connected with said lever for influencing rotation of said lever in either direction of its movement.

6. The invention as defined in claim 5 wherein said influencing means comprises an overcenter spring acting on said lever to enhance said lever movement in an overdead-center attitude.

No references cited. 

1. IN A FIREARM HAVING A FRAME AND A RECIPROCATING BARREL SLIDABLY MOUNTED THEREON FOR MOVEMENT IN RESPONSE TO RECOIL FORCES INCIDENT TO FIRING SAID FIREARM, SAID BARREL HAVING A CHAMBER FOR RECEIVING A CARTRIDGE THEREIN, AN EXTRACTOR COMPRISING A BELL CRANK LEVER PIVOTALLY MOUNTED ON SAID FRAME AND DISPOSED IN A NORMAL POSITION PRIOR TO FIRING OF SAID FIREARM REARWARDLY OF SAID BARREL CHAMBER, ONE ARM OF SAID LEVER EXTENDING NORMALLY INTO THE PATH OF SAID RECIPROCATING BARREL AND HAVING AN EXTENDED END PORTION FOR ENGAGEMENT WITH THE EXTRACTOR GROOVE OF A CARTRIDGE CHAMBERED IN SAID BARREL, A SURFACE PORTION OF SAID ONE ARM ADJACENT TO SAID EXTENDED END PORTION BEING CURVED TO PROVIDE A CAM SURFACE AND BEING DISPOSED FOR ENGAGEMENT WITH SAID BARREL IN RESPONSE TO RECOIL THEREOF, ANOTHER ARM OF SAID LEVER BEING DISPOSED FOR ENGAGEMENT BY SAID BARREL IN RESPONSE TO COUNTERRECOIL THEREOF FOR RETURNING SAID LEVER TO ITS NORMAL POSITION AND MEANS ON SAID FRAME OPERATIVELY CONNECTED WITH SAID LEVER FOR BIASING SAID LEVER IN EITHER DIRECTION OF ITS MOVEMENT INCIDENT TO RECIPROCATING MOVEMENT OF SAID BARREL. 